Steven Spielberg is executive producing two high-concept television series and has, in the past couple of years, been shepherding them to the small screen. But along the way, one – Terra Nova on Fox – was seemingly stealing all the hype.

Part of that was an enormous budget, with the 13 episodes reportedly costing $4 million each, plus shooting on location in Australia. Millions more were spent on elaborate sets. But there always seemed to be delays when Fox was preparing to show clips to critics. Production delays eventually forced Fox to drop its plan to air the pilot in May, a la the Glee launch, then return with a bang in the fall after everybody talked Terra Nova to death on social media all summer.

Oh, well.

With the big May sneak-peek doomed, along came June and, with quite a bit less fanfare, the impending premiere of Spielberg’s other series, Falling Skies on TNT.

And guess what? It’s really good.

So good and so entertaining, in fact, that the pressure is squarely on Terra Nova not to become a high-priced flop (cough, FlashForward, cough) come fall. Hey, stranger things have happened.

And when it comes right down to it, do you want your sci-fi to involve going back in time with dinosaurs or confronting a post-apocalyptic world where aliens have bombed the bejesus out of Earth?

Exactly. Let Terra Nova dabble in Jurassic danger while Falling Skies puts machine guns in the hands of kids. Or they could both be really good.

If you’re wondering about kids with machine guns, yes, it has come to that in the world of Falling Skies. The premise is that alien ships arrived – present day – and brought a whole lot of whoop-ass with them. Much of the world has been destroyed, military targets taken out, the population decimated and the aliens are an occupying force. It’s left up to ordinary citizens to fight back – kids included -- even though they are vastly outnumbered, under-armed and technologically lacking.

Falling Skies picks up six months after the carnage and part of the citizen army known as 2nd Mass (because they are in Boston) is looking for food and weapons, trying to avoid the deadly mechanized robots (known as “Mechs”) doing the killing for the multiple-legged aliens (known as “Skitters”) who launched the attack. (The aliens are hard to describe, but if you’ve seen Monsters, Inc., think about Mr. Waternoose sans color or the ability to sound like James Coburn).

The series wastes little time in setting the grim scenario: Everybody’s on their own. The resistance fighters are doing the best they can, but it’s a rag-tag collection at best, vastly overwhelmed to the point where anybody who can handle a gun gets one (if there’s one to be spared). The aliens have also kidnapped teenagers and attached a tentacled bug to their spines, which essentially turns them into zombie-like slaves.

Conceived by Spielberg and Robert Rodat (who wrote Saving Private Ryan), the series also claims Graham Yost (Justified, The Pacific) as an executive producer. Mark Verheiden (Heroes, Battlestar Galactica) and Greg Beeman (Heroes, Smallville) are co-executive producers – and hopefully they’ve learned from the wayward mistakes of Heroes as Falling Skies goes forward.

The series stars Noah Wyle as Tom Mason, a Boston history professor with a specialty in military tactics. He’s assigned to Weaver (Will Patton), the commander of 2nd Mass. Moon Bloodgood is Anne Glass, a pediatrician who lost her own family but is taking care of the children in the group. Mason has three sons – eldest teenager Hal (Drew Roy) who has become impressively battle-hardened; middle child Ben (Connor Jessup), kidnapped and “harnessed” by the aliens; and 8-year-old Matt (Maxim Knight), who has not only lost his mother, who died in the invasion, plus a brother under alien control, but he doesn’t have the ability to fully understand why his life isn’t normal.

And that’s ultimately what works best in Falling Skies. Smartly set just far enough after the attack to have the shock worn down, but not far enough for anyone to have fully recovered, emotionally, we meet these characters at an unfamiliar juncture for most sci-fi fare. Spielberg and company don’t have to recreate War of the Worlds for us to know what happened. Falling Skies shares a number of welcome similarities to the re-imagined Battlestar Galactica, in that both series have a tone that each character understands and both series accomplish a lot for what is likely a fraction of what Terra Nova is spending. This more granular approach to the apocalypse favors sharp writing and nuance. Credit Wyle with establishing exactly the right tone here – his character has lost his wife, a son is kidnapped by the aliens and instead of running around frantically, his downbeat acceptance essentially conveys, “Hey, it’s done. It happened. We didn’t dream it. This is life as we know it now.”

Of course, in that way there are also welcome comparisons to The Walking Dead as well. Falling Skies is first and foremost a survival story. The series does well by not sugarcoating reality for the children in the story. Mason’s youngest may want to celebrate a birthday and get a present, but the abiding mood is that such whimsy belongs in a past life. There’s a bigger question out there – what are the aliens up to? – plus numerous unanswered smaller questions about whether there’s a government in place, how many people are still alive, etc.

But the entertainment value and suspense of Falling Skies is paced just right. You get the sense that we’ll get those answers eventually. And yet, you want to devour the next episode immediately. You know, like a raptorsaurus.